Michael Novak, the scholar and theologian, points to a particular medieval story (best known to English speakers as Chaucer’s Tale of Melibee from “The Canterbury Tales”) as the cornerstone of modern liberal society. In the story, a man seeking revenge for terrible wrongs finally has his enemies in his power, but he is prevailed upon by his wife to resist taking vengeance.

If Professor Novak is right, we should take “Daratt,” by the Chadian director Mahamat-Saleh Haroun, as being among the more hopeful artifacts to come out of the Islamic world in recent years. As we have learned in Iraq, tribal societies in which vendettas and other sorts of “honor killing” are still commonplace is unpromising ground for democracy and liberal values to take root.

The civil war in Chad makes the one in Iraq — if that’s what it is — look like a brief scuffle. Continuing on and off more or less since the French left in 1960, it has claimed tens of thousands of victims, including members of the director’s family. His film takes this war as its setting.

During one of the periodic lulls in the fighting, a government Commission on Truth and Justice announces an amnesty for 200 war criminals. This produces riots and demonstrations. “The blood our families shed must be paid back!” a rioter shouts.

In one of the opening scenes, 16-year-old Atim Abatcha (Ali Bacha Barkäi) hears the noise of an angry crowd, then the sounds of a machine gun firing and shrieks of panic. He wanders into the village square, where the crowd has been. It is deserted except for shoes and sandals lying everywhere, left behind by people in a hurry to get away.

Atim is not obviously politically involved, but his blind grandfather, Gumar Abatcha (Khayar Oumar Defallah), summons him to tell him that, in the absence of justice from the state, the boy is going to have to take vengeance against his father’s murderer. The grandfather carefully unwraps an automatic pistol and presents it to the child. “This belonged to your father,” he says. “It has not been used for a long time.” He also warns that the man Atim must kill, Nassara (Youssouf Djaoro), is a dangerous character. Then he sends the boy off to the capital, N’Djaména, to find him.

I particularly liked the way in which Atim is at first just like any country boy arriving in the big city for the first time. He is soon befriended by Moussa (Djibril Ibrahim), who offers the boy a place to stay with his aunt (Fatimé Hadje). The two boys are soon scraping a living together with acts of petty theft. Atim acquires his first cell phone.

Atim also encounters his target for the first time and is troubled to find that Nassara is a disabled war veteran and a baker with a young, pregnant wife, Aïcha (Aziza Hisseine) — and that he hands out free bread to the poor and street people every morning outside his bakery.

Atim comes back the next day, fingering his weapon beneath his clothes, but he hasn’t got the nerve to shoot Nassara. The latter notices him hanging back behind the knot of youngsters who have come for bread and asks him what he wants. “Not charity,” Atim says proudly.

“Well, if you’re looking for work, come back tomorrow.”

He does, and Nassara takes him on as an apprentice baker. Two or three other occasions during which Atim might take his revenge are allowed to pass, and soon the relationship between the two becomes like that between father and son.

Atim’s own father had been killed before he was born — “Atim” means orphan — and his relationship with Nassara obviously fills a gap in his life. Moreover, he is proud to be learning a trade and scorns the invitation of Moussa to return to life on the streets.

On one occasion, Nassara is angered to the point of violence when he comes upon Atim and Aïcha laughing at him behind his back. Later he apologizes. “Some times I can’t control myself,” he says. “I can even be dangerous” — adding humbly, “I have done a lot of harm in my life.”

It’s a nice touch to have Nassara confirm the judgment of Atim’s grandfather, but in a context that utterly changes our understanding of its meaning. For he is also dangerous to the Abatcha family’s proj ect of revenge by being so obviously humane and penitent.

A lot of the credit has to go to Mr Djaoro’s immensely dignified and watchable performance as Nassara It is easy to see how Atim might be awed by him, even without the personal relationship that has devel oped between them, and we begin to get a bit of Western-style perspective on the primitive honor culture’s demand for vengeance.

jbowman@nysun.com

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